1. Field of the Invention
The present invention relates in general to pressure switches, and more particularly to pressures switches of a type which is installed in a hydraulic circuit of an automotive power steering device or the like.
2. Description of the Prior Art
One of the conventional pressure switches of the above-mentioned type is disclosed in Japanese Utility Model First Provisional Publication 2-80943.
The pressure switch of this publication comprises a cylindrical case, a plastic seal received in the case, and a switch proper held by the plastic seal. The switch proper includes a stationary contact, a movable contact, a biasing spring for biasing the movable contact toward the stationary contact and an operation pin for moving the movable contact away from the stationary contact in accordance with an oil pressure applied thereto. That is, upon application of oil pressure to the operation pin, the pin moves the movable contact away from the stationary contact to obtain "OFF" condition of the switch proper. Due to work of the biasing spring, under no pressure application to the operation pin, the movable contact is kept in contact with the stationary contact to achieve "ON" condition of the switch.
The above-mentioned conventional pressure switch has a drawback. That is, the stationary and movable contacts have respective cables which are welded thereto. These cables extend to a control unit. However, welding the cables to the respective contacts causes not only complicated construction of the switch but also troublesome assembly of the same.